Augustaville, Pennsylvania

Northumberland County, Pennsylvania
Northumberland County Courthouse
Location in the U.S. state of Pennsylvania
Pennsylvania's location in the U.S.
Founded	March 21, 1772
Named for	Northumberland
Seat	Sunbury
Largest city	Sunbury
Area
• Total	478 sq mi (1,238 km2)
• Land	458 sq mi (1,186 km2)
• Water	19 sq mi (49 km2), 4.0%
Population (est.)
• (2015)	93,246
• Density	204/sq mi (79/km²)
Congressional districts	10th, 11th
Time zone	Eastern: UTC-5/-4
Website	www.northumberlandco.org

Northumberland County is a county located in the U.S. state of Pennsylvania. As of the 2010 census, the population was 94,528. Its county seat is Sunbury. The county was formed in 1772 from parts of Lancaster, Berks, Bedford, Cumberland, and Northampton Counties and named for the county of Northumberland in northern England. Northumberland County is a fifth class county according to the Pennsylvania's County Code.

Northumberland County comprises the Sunbury, PA Micropolitan Statistical Area, which is also included in the Bloomsburg-Berwick-Sunbury, PA Combined Statistical Area.

Among its famous residents, Joseph Priestley, the Enlightenment chemist and theologian, left England in 1796 due to religious persecution and settled on the Susquehanna River. His former house (originally purchased by chemists from Pennsylvania State University after a colloquium that founded the American Chemical Society) is a historical museum.

By 1813 the area once comprising the sprawling county of Northumberland had been divided over time and allotted to other counties such that lands once occupied by Old Northumberland at its greatest extent are now found in Centre, Columbia, Luzerne, Lycoming, Mifflin, Union, Clearfield, Clinton, Montour, Bradford, Lackawanna, Susquehanna, Wyoming, Tioga, Potter, McKean, Warren, Venango, Snyder, and Schuylkill Counties.